The Catholic Action League of Massachusetts lashed out at Boston’s mayor Thursday for what it described as pressuring organizers to allow gays to march in the St. Patrick’s Day Parade.

C.J. Doyle, executive director of the Catholic Action League, described the inclusion of gay and lesbian groups as entirely inappropriate for a Catholic celebration and said it would destroy the traditional character of the South Boston parade.

“St. Patrick was a Catholic archbishop and is a Catholic saint,” Doyle said in a statement Thursday. “How do you honor a Catholic saint by providing a platform to those who express pride in rejecting Catholic morality? And who castigate that morality as bigotry, hatred, and homophobia?”

The Catholic Action League is an independent organization and operates separately from the Archdiocese of Boston. A spokesman for the archdiocese could not be reached Thursday night.

“The feast of St. Patrick commemorates the bishop and confessor through whom an entire people, in one lifetime, were converted from paganism to the Catholic and apostolic faith,” the statement said. “Mayor Walsh’s efforts, if successful, would destroy the traditional character of the parade, empty it of its original meaning, and reduce it to a secular community festival, devoid of any religious significance.”

The organization’s statement came after Walsh said he would not participate in the March 16 parade if gays are excluded and after Walsh said he was trying to broker a deal with the organizers, the South Boston Allied War Veterans Council, that would allow gay groups to march.

A spokeswoman for Walsh said that the Catholic Action League’s statement does not change his stance on the issue.

“As the mayor of Boston, Mayor Walsh believes he is the mayor of all citizens, and that everyone should have an opportunity to march,” spokeswoman Lisa Pollack said.

Walsh’s refusal to march would follow a similar choice by Mayor Thomas Menino.

“Marching as a state rep and celebrating my heritage is a little different,” Walsh said Wednesday. “As mayor, I feel like I should use my influence. I feel the parade should be inclusive.”

In 1995, John J. “Wacko” Hurley won a ruling at the US Supreme Court that essentially granted private organizations the right to exclude groups if they present a message contrary to what the private organization is trying to convey.

Andrew Ryan and Billy Baker of the Globe staff contributed to this report. Haven Orecchio-Egresitz can be reached at Haven.egresitz@globe.com.